We used ALOS InSAR images to study land surface deformation over the Crandall Canyon mine in Utah, which collapsed on 6 August 2007 and killed six miners. The collapse was registered as a ML 3.9 seismic event. An InSAR image spanning the time of the collapse shows 25–30 cm surface subsidence over the mine. We used distributed dislocation sources to model the deformation ﬁeld, and found that a collapse source model alone does not adequately ﬁt the deformation
ﬁeld. Normal faulting is also required, such that the event is best characterized as a ‘trapdoor’ collapse. The calculated moment of the normal fault is about the
same as the moment of the collapse source, with each larger than the seismically computed moment. Our InSAR results, including the location of the event, the extent of the collapsed area, and constraints on the shearing component of the deformation source, all conﬁrm and extend recent seismic studies of the 6 August 2007 event.